For security reasons, you may wish to prevent Excel 2003 from exchanging information with other applications that support DDE (Dynamic Data Exchange). To perform this tweak, do the following:
1. Click "Tools", selecting "Options".
2. When the "Options" multi-tabbed dialog box appears, click the "General" tab.
3. Check "Ignore other applications".
4. Click "OK" to close the dialog box.
Note that checking this option may prevent you from opening spreadsheets merely by double-clicking them in Explorer. You must first start Excel 2003, and then open the spreadsheets from within the application.
Press the "print" button on your browser or select "File" - "Print" to print this tip. Then, return to Microsoft Excel 2003 Security and Privacy - Prevent Dynamic Data Exchange.
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